Pet bottle and method of manufacturing the same

ABSTRACT

The present invention provides a PET bottle that is adapted such that a capacity of a container body can be extremely reduced when juice or mineral water in the container body is drunk off and the container body is discarded. The present invention proposes a method of manufacturing the PET bottle. In addition, the present invention makes it possible to extremely reduce cost for collection of PET bottles and personal expenses for cleaning and collection. The PET bottle is manufactured using a pair of cylindrical mold bodies for PET bottle that is formed in a bellows shape in a horizontal direction in an entire length or a part of the length in a longitudinal direction thereof excluding a mouth portion on a side in an inner periphery, is lower than a height of the PET bottle body when content is filled therein, and is drilled in a shape substantially the same as a PET bottle body.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to molding that is used in a blowmolding method, which is mainly called stretch blow or indection blow oris generally called PET resin blow, to mold a container for juice ormineral water. In particular, the present invention relates to a PETbottle, which has different heights at the time when the PET bottle isfilled with content and at the time when the PET bottle is empty, and amethod of manufacturing the same.

2. Description of the Prior Art

In recent years, a quantity of production of synthetic resin bottles hasbeen extremely large.

However, when a container body is disposed after juice or mineral waterin the container body is drunk off, the container body keeps a shapebefore the container body is drained. If the container body is thrown ina trash can, the trash can is filled with empty container bodies in ashort time as if the trash can is filled with the air. Eventually, emptycontainer bodies are thrown on the street to deteriorate the livingenvironment. In addition, cost for collection of the empty containerbodies and personal expenses for cleaning impose a significant burden onthe public service.

Further, whereas the synthetic resin bottle of this type can bemanufactured by convenient means such as blow molding, it cannot be saidthat the synthetic resin bottle has sufficient strength for withstandingan impact during transportation by an automobile or other transportationmeans involving heavy vibration and a weight at the time when syntheticresin bottles are stacked for exhibition at the store.

Moreover, when the containers are transported from a manufacture to acompany that fills juice or mineral water in the containers, cost fortransportation of the containers is significant because the containerbodies are bulky as if the air is transported.

Therefore, the inventor provided a liquid container that was worked outsuch that the liquid container could be easily reduced in size when theliquid container was collected as a waste article.

This liquid container is made of relatively soft synthetic resin, andperipheral folds of a liquid container body having a mouth portion at anupper end is formed in bellows (see Abstract of Japanese PatentApplication Laid-Open No. 2001-213418).

In addition, the inventor proposed an invention for means formanufacturing a container body in a shape, in which a capacity thereofwas substantially reduced by giving load in a vertical direction and/ora twisting direction of the container body, and maintaining this reducedshape and an invention for the container body. (see Abstract of PatentApplication Laid-Open No. 2002-68156).

As a result, the invent or could attain the above-described objects. Inother words, the inventor could further reduce a height and a capacityof the container body when the container body is crushed and keep thatstate.

In the conventional PET bottle manufacturing means, a so-calledbiaxially oriented blow molding method using a pre-form is mainly used.

For example, there is an invention for performing opening and closingoperations of a pair of molds, in which the pre-form can be set, with aring and a rotating disc that are axially provided so as to be capableof rotating 180° (see pages 3 and 4 of Japanese Patent ApplicationLaid-Open No. 11-48327). However, there is almost no invention for a newand excellent mold for manufacturing bellows of the container body andfolds constituting the bellows and a method of manufacturing the mold.

However, a well-known invention for subjecting a pre-form, which is aprimary molded product formed in a predetermined shape in advance, tobiaxially oriented blow molding with a primary blow mold to form aprimary intermediate molded product, subjecting the primary intermediatemolded product to heat processing to force the primary intermediatemolded product to thermally shrunk and deformed into a secondaryintermediate molded product, and subjecting the secondary intermediatemolded product to secondary blow molding to form a bottle or othercontainers by hardly extending and deforming the secondary moldedproduct compared with primary blow (see page 2 of Japanese Patent No.2777790).

SUMMARY OF THE INVENTION

In general, it is an object of the present invention to provide a PETbottle that can be reduced in capacity when juice or mineral water in acontainer body is drunk off and the container body is discarded.Moreover, the present invention proposes a method of manufacturing thePET bottle. The number of container bodies manufactured by the method,which are put in a trash can, is remarkably increased compared withcontainer bodies that cannot be put in a trash can in a sufficientlylarge number. This makes it possible to transport a large number ofempty container bodies simultaneously. Thus, cost for collection of thecontainer bodies and personal expenses for cleaning and collection canbe reduced remarkably.

In addition, a mold for such a container body is suitable formanufacturing a large number of container bodies, and a bellows portionand folds constituting the bellows are formed surely. As a result, a PETbottle, which is adapted to keep a crushed state when the container bodyis crushed, and a method of manufacturing the PET bottle could beproposed.

In general, the present invention is characterized by molding used for ablow molding method, which is mainly called stretch blow or indectionblow or is generally called PET resin blow, to mold a PET bottle, whichis a bottle for juice or mineral water. In particular, the presentinvention provides a PET bottle having different heights at the timewhen it is filled with content and at the time when it is empty, whichhas a smaller height compared with a height in the case in which it isfilled with juice or mineral water and is excellent in appearance, andis worked out such that height and capacity thereof can be reduced whenthe PET bottle is transported from a manufacturer thereof to a companythat fills juice or mineral water therein, and proposes a method ofmanufacturing the same.

A characteristic as means for the above is that a PET bottle havingdifferent heights at the time when it is filled with content and at thetime when it is empty could be provided, which is characterized by beingmanufactured using a pair of cylindrical mold bodies for PET bottle thatis formed in a bellows shape in a horizontal direction in an entirelength or a part of the length in a longitudinal direction thereofexcluding a mouth portion on a side in an inner periphery, is lower thana height of a PET bottle body when content is filled therein, and isdrilled in a shape substantially the same as the PET bottle body.

In addition, another characteristic of the present invention is that amethod of manufacturing a PET bottle body, which has the same inner andouter shapes as the shape of an inner peripheral side of the mold body,could be proposed using a pair of cylindrical mold bodies for PET bottlethat is formed in a bellows shape in a horizontal direction in an entirelength or a part of the length in a longitudinal direction thereofexcluding a mouth portion on a side in an inner periphery, is lower thana height of the PET bottle body when content is filled therein, and isdrilled in a shape substantially the same as a PET bottle body, andguiding a pre-form, which is a preliminary molded production formed in apredetermined shape in advance, to the mold body and subjecting thepre-form to heat processing to force the pre-form to thermally expand.

As another characteristic of the present invention, the cylindrical moldbodies include: ring shape mold pieces that have the same height as thefolds of the bellows shape, respectively, and are divided into two tothe left and right in the horizontal direction; a movable mold that isconstituted by putting the ring shape mold pieces one on top of anotherin substantially the same number as the number of the folds of thebellows shape; a coupling member that couples the ring shape mold piecesadjacent to each other vertically such that the ring shape mold piecesare in contact closely or are slightly spaced apart from each other; andan opening/closing mechanism that operates this coupling member toperform action for causing the ring shape mold pieces adjacent to eachother to come into contact or to form a space.

As another characteristic of the present invention, the pre-form is PETbottle resin.

Moreover, as another characteristic of the present invention, the PETbottle body is formed of memory resin that memorizes a height at thetime when the PET bottle body is empty.

Note that the present invention is naturally applied to a container bodythat has a mouth portion at an upper end, a small width in a heightdirection of a bottom, and a flat portion provided in an intermediatepart, and an entire length or a part of the length in a longitudinaldirection excluding the mouth portion, the width in the heightdirection, and the flat portion is formed in a bellows shape in ahorizontal direction. It is considered within a technical scope of thepresent invention that an entire shape of the container body is selectedfrom columnar including elliptical, prism including rectangular, coneand pyramid including beheaded, hourglass drum-shaped, and barrel shapedappropriately, a horizontal sectional shape of the container body isselected from circular including elliptical and square includingrectangular appropriately, and the present invention can be applied tomanufacturing means for a container that can wind a label, on which aguidance for content in a container, a trademark, or the like isprinted, to an outer periphery of the container body.

Note that the present invention has other excellent objects,characteristics, and actions and effects of the invention, which will beclarified in the following explanation of embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a front view of an entire body, which is manufactured by anapparatus and a method of the present invention, immediately aftermanufacture;

FIG. 1B is front view of an entire PET bottle body, which ismanufactured by an apparatus and a method of the present invention, in astate in which content is filled therein;

FIG. 2 is an enlarged sectional explanatory view of a fold constitutingthe PET bottle body;

FIG. 3 is a sectional view showing a shoulder portion immediately afterthe PET bottle body is manufactured;

FIG. 4 is a sectional view showing a state of an intermediate portion ofthe PET bottle body;

FIG. 5 is a sectional view showing a state of a bottom of the PET bottlebody;

FIG. 6 is a partially cutaway sectional view showing a deformed state atthe time when the PET bottle body is crushed;

FIG. 7 is a vertical sectional explanatory view of a mold body of anembodiment of the present invention and an apparatus therefor;

FIG. 8 is a half vertical sectional view of the same showing a state inwhich gaps among folds are closed;

FIG. 9 is a half vertical sectional view of the same showing a state inwhich the gaps among the folds are opened;

FIG. 10 is a sectional explanatory view in an initial state in which acontainer body has expanded; and

FIG. 11 is an enlarged sectional view showing a state in which resinenters gaps between adjacent movable molds, and the container body iscrushed in the state of FIG. 10.

DESCRIPTION OF SYMBOLS

A, Trunk

A1, Trunk including a central portion and a lower portion

B, Bottom surface portion of a container body (1)

C, Shoulder portion of the container body (1)

D, (Bell-shaped) Coupling portion

E, (Annular) groove

d, Outer diameter of the container body 1

d1, Outer diameter of a bellows shape 5 on a first stage

d2, Outer diameter of a bellows shape 6 on a second stage

d3, Outer diameter of a bellows shape 7 on a third stage

h1, Upper part of a fold on a first stage

h2, Lower part of the fold on the first stage

1, PET bottle body

2, Bellows shape

3, Mouth portion

4, Split spherical shape

5, Bellows shape on a first stage

6, Bellows shape on a second stage

7, Bellows shape on a third stage

8, Bellows shape on a fourth stage

10, Projected arc shape

11, Linear shape

12, Cap

13, Crest

14, Trough

15, Upper surface of an abacus bead shape

16, Lower surface of the abacus bead shape

101, Metal body

102, Pre-form

103, Ring-shaped piece

104, Upper split mold

105, Lower split mold

106, Movable mold

107, Gap

108, X-shaped coupling member

109, Linear member

110, Mold frame

111, Piston body

112, Crank member

113, Intermediate portion

114, Cam member

115, Taper

116, Coil spring

117, Fold mold

118, Crest mold

119, Trough mold

120, Bell shape

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the figures, reference numeral 1 denotes a PET bottle body that isobtained according to a manufacturing method of the present invention.In explaining embodiments of the present invention with reference to theaccompanying drawings, first, a structure and actions and effects of thePET bottle itself will be explained because characteristics of thepresent invention is easily understood if the structures and the actionsand effects are understood.

In the PET bottle body 1 shown in FIG. 1A, in a state in which the PETbottle body 1 is taken out from a manufacturing apparatus therefor, aheight excluding a mouth portion at the top is A, and an outer peripheryand an inner periphery in a length direction are formed in a bellowsshape 2. In this case, as a matter of comparison, the height A of thisPET bottle body 1 is molded to be small, in other words, the PET bottlebody 1 is molded with, for example, a capacity of 200 ml even if the PETbottle body 1 has a capacity of 500 ml when content is filled therein.

The PET bottle body 1 with the small capacity in the height A directionis transported in this state of a cap and sent to, for example, afactory for filling mineral water. In this case, since the PET bottlebody 1 with the small capacity is transported rather than the empty PETbottle body 1 with the capacity of 500 ml, a larger number of PET bottlebodies can be transported simultaneously.

The low PET bottle body 1 transported to the factory is changed to thePET bottle body 1 having a regular height A as shown in FIG. 1B bysending liquid other than the air into the PET bottle body 1 in advance,or goods with liquid sent into the PET bottle 1 is transported.

Now, a person removes a cap 12 and drinks content. Since the PET bottlebody 1 of the present invention is formed in a bellows shape pulled in aheight direction in work for filling the mineral water or the like, theheight of the PET bottle body 1 is reduced by an amount of the drunkenmineral water even when a person is drinking the mineral water.

Certainly, it is difficult even for a young person to drink off themineral water filled in the PET bottle body 1 with a capacity of 200 mleach time. In addition, it is trouble to carry the PET bottle with acapacity of 200 ml in a half empty state, and the PET bottle is oftenthrown away after all. In this regard, if the height of the PET bottleis reduced by an amount of the drunken mineral water every time themineral water is drunk, it is very convenient to carry the PET bottleby, for example, packing the PET bottle in a handbag. However, as anactual problem, even if the PET bottle body 1 is formed in a shape ofbellows, it is difficult to reduce the size of the PET bottle body 1 by70 to 90% from the regular height only by a restoring force of theshape.

Thus, after, for example, the mineral water in the PET bottle body 1 isdrunk off, an external force is applied to the PET bottle body 1 tocrush the PET bottle body 1 from one side or both sides in a height(length) direction thereof. This state is shown in FIGS. 2 and 3.

In other words, the present invention has an excellent structure andshows an excellent action in order to bring the PET bottle body 1 into arestored state with the original height when a person is drinking themineral water or the like in the PET bottle body 1 and in order to keepthe crushed state.

As an example of the structure of the container, reference numeral 3denotes a mouth portion of the container body 1 having a male screwcarved in an outer periphery thereof. The mouth portion has a diameterof about 28 mm and a height of about 23 mm. In addition, immediatelybelow the mouth portion, a bell-shaped coupling portion (D) having aheight of 5 to 10 mm with a diameter expanded to about 51 mm in a lowerpart thereof is connected on an axis of the mouth portion 3.

There is a U-shaped annular groove E with a horizontal inner end in ashoulder portion C of the container body 1. An end of the bell-likecoupling portion D and a side on the inside of the annular groove E arecoupled.

In addition, a side on the outside of the U-shaped groove E is formed ina split spherical shape 4 facing downward. An outer diameter d1 of abellows shape 5 in a first stage, that is, an outer diameter d1 on anuppermost stage of the bellows shape 2 is set to smaller than an outerdiameter d of the container body 1.

An outer diameter d2 of a bellows shape 6 on a second stage is largerthan the outer diameter d1 of the bellows shape 5 on the first stage andsmaller than the outer diameter d of the container body 1.

The side on the outside of the U-shaped groove E is formed in a stepshape viewed from the side such that an outer diameter d3 of a bellowsshape 7 on a third stage is larger than the outer diameter d2 of thebellows shape 6 on the second stage and smaller than the outer diameterd of the container body 1. However, it is needless to mention that theside is not limited to three stages but may be plural stages accordingto circumstances. In the embodiment shown in the figures, it is assumedthat the side is formed in the three stages.

More specifically, in the container shown in FIG. 1, the container body1 with a height of 195 mm, a maximum diameter of 71.5 mm, and a capacityof 500 ml is formed in a shape having folds of twelve stages.

However, in this case, the outer diameter d1 of the bellows shape 5 onthe first stage is set to 60.5 mm, and the outer diameter d2 of thebellows shape 6 on the second stage is set to 67.0 mm. A diameterbetween the bellows shape 5 on the first stage and the bellows shape 6on the second stage is set to 47 mm.

Similarly, the outer diameter d3 of the bellows shape 7 on the thirdstage is set to 69.0 mm, and an inner diameter between the bellows shape6 on the second stage and the bellows shape 7 on the third stage is setto 51.1 mm.

Moreover, an outer diameter d of a bellows shape 8 on a fourth stage,which is equal to the maximum outer diameter of the container body 1, isset to 71.5 mm, and an inner diameter between the bellows shape 7 on thethird stage and the bellows shape 8 on the fourth stage is set to 54.5mm.

Outer diameters of bellows shapes on fifth to twelfth stages below thefourth stage are the same as the outer diameter d of the bellows shapeof the fourth stage. Inner diameters of adjacent two bellows shapes areidentical with the inner diameter between the bellows shape 7 on thethird stage and the bellows shape 8 on the fourth stage.

In this case, the folds take a shape like an unidentified flying object(UFO) called the Adamski type. Therefore, the folds are verticallydivided into two in the horizontal direction.

In this case, in the figure, heights of an upper part (h1) and a lowerpart (h2) of the fold on the first stage are 6.5 mm and 5.5 mm, those ofthe fold on the second stage are 7 mm and 5 mm, and those of the fold onthe third stage are 8.5 mm and 6.5 mm.

More specifically, a sectional shape of these folds is shown in FIG. 4and other figures.

That is, this is an example of dimensions of the folds on the firststage 5 to the third stage 7. In the figure, it is important that ashape of an upper surface 15 of a wide abacus bead shape is a bay shapeprojecting to an outer direction with 20 mmR in this embodiment, whereasa lower surface 16 is formed in a linear shape 11 via a projected arcshape 10 with 0.8 mmR.

To explain this structure of this embodiment together with an actionthereof, in general, the PET bottle body 1 in the state of FIG. 1 isdivided into a trunk portion A1 including a central part and a lowerpart and a shoulder portion C on the upper part as shown in FIG. 6. Incomparison of the portions A1 and C, since diameters of the portions A1and C consist of large and small diameters, a stable vertical state ismaintained.

That is, the trunk portion A1 including the central part and the lowerpart is formed by an identical fold in inner and outer diametersthereof. The shoulder portion C is bent in a protruded shape with agentle inclination in a direction of the mouth portion 3 in appearance.In particular, in the shoulder portion C, an inner diameter of a trough14 forming the fold is gradually reduced from the central part to themouth portion 3, and a difference of an angle of inclination thereof ismade larger than that of the trunk portion A1. Thus, in a state in whichthis central part extends, even when a person is drinking content, innerdiameters and slopes of a crest 13 and the trough 14 forming the foldcan keep the state of reduced heights with strength and an elastic forceinherent in a material.

Consequently, the shoulder portion C and the trunk portion A1 of the PETbottle body 1 presses the folds of the shoulder portion C, which wouldbe in a shrunk state due to a restoration force thereof, and an end faceof the trough 14 compresses a trough end face of the folds locatedadjacent to each other in a vertical relation.

In a state viewed from the peak of the crest 13 of the fold at thispoint, this is equivalent to a state in which the troughs 14 on bothsides are pushed to the peak side of this crest 13. In this case, sincean upper surface 15 of the fold is less inclined compared with a lowersurface 16, a compression component of force on a gentle inclinationside is larger than a compression component of force on a steepinclination side of the lower surface 16, the trough 14 on the steepinclination side moves to the peak side of the crest 13.

At this point, two significant changes occur in the container body 1.

A first change is an increase in the inner diameter of the crest 13constituting the fold due to an expansion pressure or a decrease in theinner diameter of the trough 14 due to a compression pressure. A secondchange is bending of the steep side of the lower surface 16 constitutingthe fold.

Subsequently, when this steep inclination side passes right below thecrest 13 and further creeps into the inside on the gentle inclinationside of the upper surface 15 as shown in FIG. 5 to move the height ofthe container body 1 to a reduced state, a force of restoring the innerdiameter of the crest 13 and the inner diameter of the trough 14 worksor to restore the lower surface 16, which is in a bent state due to theabove-described operation, to an extended state and stabilize the lowersurface 16.

Therefore, even if a compression force is not always applied, thisreduced state could be kept.

Then, the trough 14 with a small inner diameter is subjected to acompression pressure to be further reduced in the inner diameter,whereby a pressure stress occurs.

When the compression pressure disappears, a stress acts so as to openthe trough 14 and restores the trough 14 to the extended state.

Thus, the PET bottle body 1 maintains a reduced state under theatmospheric pressure. In the case in which a compression stress does notoccur due to a difference of the inner diameter of the trough 14, thePET bottle body 1 maintains the reduced state.

As a result, in repeated experiments, a height (capacity) of thecontainer body 1 decreased to ¼ to ⅛. Even if the container body 1 wasthrown in a trash can, a space occupied by the container body 1 could bereduced remarkably.

Next, an embodiment of a mold, with which the characteristics and theexcellent actions and effects in the PET bottle body 1 of the presentinvention can be shown and which is suitable for mass production of thecontainer body 1, will be described.

In the figure, reference numeral 101 denotes a cylindrical mold bodydivided into two. A pre-form 102 can be inserted from a bottom surfacethereof.

This mold body 101 is constituted by ring-shaped mold pieces 103 ofseveral stages staked in a height direction.

The ring-shaped mold pieces 103 formed in a disc shape divided into twoin a horizontal direction. A lowest stage thereof is an upper split mold104 in which molds for forming the container body 1, the mouth portion3, and the split spherical shape portion 4 are carved. A lowest stagethereof is a lower fixed split mold 105 in which a mold for forming thebottom of the container body 1 is carved. Between the upper spit mold104 and the lower fixed split mold 105, there are movable molds 106equivalent to the number of folds for forming the bellows shapes 2 ofthe container body 1.

A height of a split mold for the PET bottle body carved in this moldbody 101 is lower than the height at the time when content such asmineral water is actually filled in the PET bottle body.

Usually, there are slight gaps 107 between the upper and lower splitmolds 104 and 105 and the movable molds 106 and between the adjacentmovable molds 106. When a part of a swell of the pre-form 102 enters thegaps 107 slightly, the gaps 107 are closed.

Various structures are possible as this structure.

For example, an intermediate part of an X-shaped coupling member 108 ispivotally attached to both sides of the upper split mold 104, themovable molds 106, and the lower fixed split mold 105.

This X-shaped coupling member 108 can be formed by respective linearmembers 109 with the pivotally attached portion as a fulcrum. Therespective both ends are pivotally attached to both ends of the linearmembers 109 which are adjacent to each other in a vertical relation.

As a result, as shown in FIG. 9, the characters “X” of the X-shapedcoupling member 108 are coupled in the vertical direction on the side ofthe mold body 101.

In addition, in the figure, reference numeral 110 denotes a mold framethat is provided in contact with both sides of the mold body 101 andguides the movable molds 106. An upper part thereof is provided abovethe mold body 101 and is provided with a piston body 111, upper andlower parts of which are guided by the mold frame 110.

An end of this piston body 111 is in contact with an upper end of theX-shaped coupling member 108 and performs an action for pressing thecoupling member 108 downward.

An end of a usually V-shaped crank member 112, an intermediate portion113 of which is pivotally attached, is pivotally attached to an upperpart of the piston body 111. An upper end of the crank member 112 ispivotally attached to the mold frame 110.

Reference numeral 114 denotes a cam member that moves up and down withmeans provided in parallel with the coupling member 108 appropriately. Aside of the cam member 114 is in contact with the intermediate portion113 of the crank member 112, and a taper 115 is formed in an axialdirection at a tip thereof.

When the cam member 114 as shown in FIG. 8 is not in contact with theintermediate portion 113 of the crank member 112, the crank member 112forms a V-shape. However, when the cam member 114 falls, the taper 115presses the intermediate portion 113 of the crank member 112, and thecrank member 112 takes a linear shape or a shape close to the linearshape in a vertical direction, the crank member 112 presses the upperend of the X-shaped coupling member 108 downward via the piston body111. As a result, the gaps 107 of the movable molds 106 are closed.

Note that in the figure, reference numeral 116 denotes a coil spring, anend of which is fastened to the lower split mold 115 of the mold body101, an upper part thereof passes through the movable molds 106, and anupper end thereof is fastened to the upper spit mold 104 of the moldbody 101. A force in a direction of opening the gaps 107 between theupper split mold 104 and the movable molds 106 usually acts on the coilspring 116.

In addition, in FIG. 11, in a fold mold 117 carved inside the movablemolds 106 and the lower split mold 105, a part to be the trough 14 ofthe fold constituting the bellows shape 2 of the container 1 is formedas a crest mold 118. A part between the movable molds 106 overlappingeach other or adjacent to each other in the vertical relation is formedas a trough mold 119 for constituting the crest 17 of the fold of thecontainer body 1.

In this case, a coupling portion between the mouth portion 3 of thecontainer body 1 and the container body 1 is formed in a bell shape 120in order to mold this, and the mold body 101 is constituted so as toreverse and cause the coupling portion to penetrate into the containerbody 1.

A fold mold 117 for the mouth portion 3 is formed in a wide shape likethe Adamski UFO so as to realize the container body 1 that can reduce aheight (i.e., capacity) thereof sufficiently even if the mouth portion 3is not crushed and forced into the container body 1. Therefore, the foldmold 117 is vertically divided into two in a horizontal direction, andshapes of upper and lower parts thereof are specifically common to thecontainer body 1.

To explain a process of manufacturing the container body 1 using themold body 101 in this embodiment, the gaps 107 of the movable molds 106are in the opened state.

In this state, the pre-form 102 is inserted into the mold body 101 fromthe bottom thereof.

At the same time, sufficiently heated air is sent into the pre-form 102to swell the pre-form 102.

As a result, the pre-form 102 comes into contact with the mold insidethe mold body 101 to mold the container body 1. However, a part of thepre-form 102 enters the gaps 107 between the upper and lower split molds104 and 105 and the movable molds 106 and between the adjacent movablemolds 106.

Here, the cam member 114 is lowered by appropriate means, and the taper115 in the lower part thereof presses the intermediate portion 113 ofthe crank member 112 little by little.

As a result, the crank member 112 is straightened gradually. A force ofthe crank member 112 presses the upper end of the X-shaped couplingmember 109 downward via the piston body 111.

As a result, a part of the resin of the container body 1, which hasentered the gaps 107 between the upper and lower split molds 104 and 105and the movable molds 106 and between the adjacent movable molds 106, iscrushed as shown in FIG. 10.

Whereas the trough 14 constituting the fold of the container body 1 wasmolded only through contact with the mold on the inner surface of themold in the past, the substantially V-shaped trough 14 is crushed upwardand downward to be doubled as shown in the figure in addition to forminga natural fold according to the mold.

As a result, the container body 101, which is molded by the mold body101 of this embodiment, is easily crushed in the trough 14 thereof, thecrushing work can be performed with a finger tip with little power toreduce a height (capacity) of the container body 101.

Note that, in the mold body 101, the cam member 114 rises when thecontainer body 1 is manufactured, the crank member 112 returns to theoriginal V-shape, the gaps 107 are formed between the adjacent movablemolds 106 by a restoring force of the coil spring 116. After thecontainer body 1 is removed, the mold body 101 comes into a state forrepeating the work for manufacturing a new container body.

The PET bottle body 1 obtained in this way is provided with theabove-described characteristics of the present invention and realizesthe above-described excellent actions and effects.

As another embodiment, it is possible that memory resin is used for theresin material itself forming the PET bottle body 1.

Shape memory in this context generally means a characteristic of the PETbottle body 1 that softens to return to a restored form thereof when apressure of hot air for filling content therein is applied thereto orthe PET bottle body 1 is humidified to humidity higher than usual, forexample, content with relatively high humidity is filled forsterilization or the like. Plastic having such a characteristic isreferred to as shape memory resin.

The PET bottle body 1 molded in a low state changes to, for example, thePET bottle body 1 of a predetermined height with a capacity of 500 mlwhen content is filled therein. Thereafter, even if the PET bottle body1 is placed under the normal temperature or cooled, the height or thelike is never reduced because the PET bottle body 1 is filled with thecontent.

However, when an empty portion is formed in the PET bottle body 1 or thePET bottle body 1 is drained, for example, the content is drunk off, thePET bottle body 1 returns to the original low shape.

The resin material may be polystyrene that is frequently used as amaterial for the PET bottle body 1. This is because polystyrene has acharacteristic that it is hard under the normal temperature but softenswhen temperature is raised. Moreover, polystyrene shows a characteristiclike rubber that softens when temperature is raised, that is, arestoring force of returning to an original shape when temperature rises

Note that temperature at which such a change occurs is referred to as“glass transition point” meaning that a material changes from a glassstate to a soft rubber state. Since all kinds of resin have this glasstransition point, when the present invention is implemented, it isadvisable to select and use most excellent resin having such acharacteristic. In addition, polyethylene softens in the same mannerwhen it is heated.

The resin returns to the original shape because the resin performscrosslinking reaction to fix molecules each other in a mesh shape. Theshape memory resin has a characteristic that is a combination of acharacteristic of a plastic material that hardness is changed accordingto temperature and a characteristic that a shape can be prevented fromchanging by crosslinking.

A certain material is formed in a desired shape in advance, and a shapethereof is fixed by the crosslinking reaction. When this material isheated to the glass transition temperature or a temperature, at whichthe material softens, equal to or higher than the melting point to bedeformed into a different shape and is cooled in that state, thematerial changes to the glass state or crystallizes to be hard and fixedin that shape. When this material is heated again to the glasstransition temperature or the temperature equal to or higher than themelting point, the material softens to show a rubber-like characteristicand is about to return to the shape fixed by the crosslinking reactionin advance. This is a mechanism of the shape memory.

In this way, the shape memory resin utilizes the two characteristics,that is, the change in hardness according to temperature and the fixingof a shape by the crosslinking reaction. Theoretically, the shape memoryperformance is developed by utilizing the characteristic that hardnesschanges at two different temperatures. Other than the crosslinking andthe melting point, a method of utilizing a combination of the glasstransition temperature and the melting point is also possible.Consequently, various plastics (polymeric materials) can be applied asthe shape memory resin.

As described above, in the present invention, when a PET bottle ismanufactured, a height (capacity) thereof is low (small) compared with acase in which content such as mineral water is filled in the PET bottle.Thus, when the PET bottles are transported for filling content, aquantity of PET bottles to be transported can be increased compared withthat in the past.

As a result, in general, advantages of the present invention are that,in a PET bottle body that is formed in a bellows shape in a horizontaldirection in an entire length or a part of the length in a longitudinaldirection thereof excluding a mouth portion at an upper end and a smallwidth in a height direction of a bottom, when juice or mineral water inthe PET bottle body is drunk off and the PET bottle body is discarded, acapacity of the PET bottle body is reduced, and as a result, a largequantity of empty bottles can be discarded in a fixed area compared withthat in the past.

In addition, since products on the market as a container for drinkusually has a capacity of 500 ml, contents in the container is rarely“drunk off” at a time.

Therefore, the container including an empty part, the capacity of whichnever changes even if the content remains, has to be carried.

In this regard, since the container of the present invention can becarried with an empty part compressed, the container can be easilypacked even in a handbag.

Moreover, the container body of the present invention looks nice in anexternal shape thereof to significantly attract users' interest. A shapeof bellows in the container body can function as slip resistance toprevent the container body from slipping to fall during use or preventcontent from excavating.

Main advantages of the container body described above are that, when thecontainer body is discarded, a capacity thereof can be extremelyreduced, and the number of container bodies, which can be put in a trashcan or the like, is extremely increased.

In addition, since such a compressed container body can be transportedin a large quantity at a time, cost for collection of container bodiesand personal expenses for cleaning and collection can be extremelyreduced.

1. A PET bottle having different heights at the time when the PET bottleis filled with content and at the time when the PET bottle is empty,wherein the PET bottle is manufactured using a pair of cylindrical moldbodies for PET bottle that is formed in a bellows shape in a horizontaldirection in an entire length or a part of the length in a longitudinaldirection thereof excluding a mouth portion on a side in an innerperiphery, is lower than a height of a PET bottle body when content isfilled therein, and is drilled in a shape substantially the same as thePET bottle body.
 2. A method of manufacturing a PET bottle havingdifferent heights at the time when the PET bottle is filled with contentand at the time when the PET bottle is empty, wherein the methodmanufactures a PET bottle body using a pair of cylindrical mold bodiesfor PET bottle that is formed in a bellows shape in a horizontaldirection in an entire length or a part of the length in a longitudinaldirection thereof excluding a mouth portion on a side in an innerperiphery, is lower than a height of the PET bottle body when content isfilled therein, and is drilled in a shape substantially the same as aPET bottle body, and guiding a pre-form, which is a preliminary moldedproduction formed in a predetermined shape in advance, to the mold bodyand subjecting the pre-form to heat processing to force the pre-form tothermally expands.
 3. The method of manufacturing a PET bottle havingdifferent heights at the time when the PET bottle is filled with contentand at the time when the PET bottle is empty, according to claim 2, =p1wherein the cylindrical mold bodies include: ring shape mold pieces thathave the same height as the folds of the bellows shape, respectively,and are divided into two to the left and right in the horizontaldirection; a movable mold that is constituted by putting the ring shapemold pieces one on top of another in substantially the same number asthe number of the folds of the bellows shape; a coupling member thatcouples the ring shape mold pieces adjacent to each other verticallysuch that the ring shape mold pieces are in contact closely or areslightly spaced apart from each other; and an opening/closing mechanismthat operates this coupling member to perform action for causing thering shape mold pieces adjacent to each other to come into contact or toform a space.
 4. The method of manufacturing a PET bottle havingdifferent heights at the time when the PET bottle is filled with contentand at the time when the PET bottle is empty, according to claim 2,wherein the pre-form is PET bottle resin.
 5. The method of manufacturinga PET bottle having different heights at the time when the PET bottle isfilled with content and at the time when the PET bottle is empty,according to claim 2, wherein the PET bottle body is formed of memoryresin that memorizes a height at the time when the PET bottle body isempty.
 6. The method of manufacturing a PET bottle having differentheights at the time when the PET bottle is filled with content and atthe time when the PET bottle is empty, according to claim 3, wherein thepre-form is PET bottle resin.
 7. The method of manufacturing a PETbottle having different heights at the time when the PET bottle isfilled with content and at the time when the PET bottle is empty,according to claim 3, wherein the PET bottle body is formed of memoryresin that memorizes a height at the time when the PET bottle body isempty.
 8. The method of manufacturing a PET bottle having differentheights at the time when the PET bottle is filled with content and atthe time when the PET bottle is empty, according to claim 4, wherein thePET bottle body is formed of memory resin that memorizes a height at thetime when the PET bottle body is empty.
 9. The method of manufacturing aPET bottle having different heights at the time when the PET bottle isfilled with content and at the time when the PET bottle is empty,according to claim 6, wherein the PET bottle body is formed of memoryresin that memorizes a height at the time when the PET bottle body isempty.